I have a carpet in my tank. I don' t think you can kill them. I dropped mine in a parking lot an hour away from my house, bag busted, he had dirt and stuff all over him, I knew he was a gonner, that was 7 month ago. I have MH, PC lighting, he will go where he wants, and kill any shrimp and probably any smaller fish that gets in him, but they are pretty easy to take care of. I feed my Mysis, and shrimp from the grocery store, he will eat anything. good luck